LOCATION BOGUSRIM                OR

Tentative Series
Rev. MLK/PWB/JBF
10/2018

BOGUSRIM SERIES

The Bogusrim series consists of moderately deep over duripan, well drained soils that formed in mixed volcanic ash and loess over residuum weathered from volcanic rock. Bogusrim soils are on lava plateaus. Slopes are 2 to 15 percent. The mean annual precipitation is about 250 mm and the mean annual temperature is about 7 degrees C.

TAXONOMIC CLASS: Fine, smectitic, mesic Abruptic Xeric Argidurids

TYPICAL PEDON: Bogusrim cobbly ashy silt loam, rangeland. (Colors are for dry soil unless otherwise noted.) The soil surface is partly covered by 5 percent stones and 2 percent cobbles.

A--0 to 10 cm; light brownish gray (10YR 6/2) cobbly ashy silt loam, brown (10YR 4/3) moist; weak thick platy structure; slightly hard, friable, slightly sticky and slightly plastic common fine and very fine roots; 10 percent cobbles and 5 percent stones; slightly alkaline (pH 7.6); abrupt smooth boundary. (3 to 30 cm thick)

Bt1--10 to 21 cm; dark yellowish brown (10YR 4/4) silty clay loam, dark yellowish brown (10YR 4/4) moist; moderate medium and fine prismatic structure; slightly hard, friable, moderately sticky and moderately plastic; common fine and very fine roots; 50 percent pressure faces; 5 percent stones; neutral (pH 7.0); clear smooth boundary. (4 to 49 cm thick)

Bt2--21 to 52 cm; dark yellowish brown (10YR 4/4) silty clay loam, dark yellowish brown (10YR 4/4) moist; strong medium and fine subangular blocky structure; moderately hard, firm, moderately sticky and moderately plastic; common fine and very fine roots; 60 percent pressure faces; 5 percent gravel and 5 percent cobbles; slightly alkaline (pH 7.8). (7 to 41 cm thick)

Bk--52 to 82 cm; very pale brown (10YR 8/3) loam, pale brown (10YR 6/3) moist; weak medium and fine subangular blocky structure; hard, very firm, nonsticky and nonplastic; strongly effervescent; moderately alkaline (pH 8.0). (4 to 60 cm thick)

Bkqm1--82 to 111 cm; cemented material; light yellowish brown (10YR 6/4) moist; massive; rigid, nonsticky, nonplastic; strongly cemented by secondary silica and calcium carbonate; violently effervescent; strongly alkaline (pH 8.6). (2 to 55 cm thick)

Bkqm2--111 to 130 cm; cemented material; massive; rigid, very strongly cemented by secondary silica and calcium carbonate; violently effervescent; strongly alkaline (pH 8.6). (19 to 38 cm thick)

R--130 cm; indurated volcanic rock

TYPE LOCATION: Malheur County, Oregon; Approximately 6 miles northwest of Arock, Oregon; about 2,200 feet north and feet west of the southeast corner section 33, T. 28 S., R. 42 E.; USGS Bogus Bench 7.5 minute quadrangle, latitude 43 degrees 5 minutes and 39.8 seconds north and longitude 117 degrees 34 minutes and 47.3 seconds west; WSG84 Decimal Degrees 43.094389 latitude and -117.579806 longitude.

RANGE IN CHARACTERISTICS:
Soil Moisture: The soil moisture control section is dry throughout in summer and fall and moist in winter and spring; aridic soil moisture regime that borders on xeric.
Soil Temperature: 8 to 9 degrees C.
Depth to Duripan: 50 to 100 cm.
Depth to Bedrock: 71 to 140 cm.
Other Features: Abrupt textural change is present between A and Bt horizons,

Particle-size control section: Clay content - Averages 35 to 55 percent.
Rock Fragments: 5 to 35 percent.

A horizons
Value: 5 or 6 dry, 3 through 5 moist.
Chroma: 2 or 4 dry or moist.
Reaction: Neutral through slightly alkaline.
Clay content: 10 to 20 percent.
Volcanic glass: Volcanic glass is estimated to range from 5 to 10 percent of the 0.02 to 2 mm fraction.

Bt horizons
Value: 3 to 6 dry, 3 to 5 moist.
Chroma: 3 to 6 dry or moist.
Texture: Silty clay loam, Clay loam, or clay.
Clay content: 35 to 55 percent.
Rock fragments: Averages 5 to 35 percent, mainly gravel and cobbles or stones.
Reaction: Neutral through moderately alkaline.

Bk horizon
Value: 5 or 8 dry, 3 through 6 moist.
Chroma: 3 or 4 dry, 3 through 6 moist.
Texture: Loam, sandy loam, or clay loam.
Clay content: 18 to 35 percent.
Rock fragments: Averages 5 to 35 percent, mainly gravel and cobbles.
Reaction: Slightly alkaline through moderately alkaline.

Bkq horizon (when present)
Value: 7 or 8 dry, 4 to 6 moist.
Chroma: 3 or 6 moist.
Texture: Loam, sandy loam, or sandy clay loam.
Clay content: 10 to 28.
Clay content: Average 0 to 30 percent, mainly gravel and cobbles.
Reaction: Slightly alkaline through moderately alkaline.
Other features: Some Bkq horizons have discontinuous weak to moderate cementation

Bkqm horizons
Value: 5 through 8 dry, 5 or 6 moist.
Chroma: 2 through 6 dry, 3 to 6 moist.
Effervescence: Strongly effervescent through violently effervescent.
Reaction: Slightly alkaline through strongly alkaline.
Cementation: Strongly cemented to very strongly cemented.

COMPETING SERIES: These are the Catchell, Chilcott, Lookout, Lovejoy, Novacan, Pigtail, Reno, and Suncold soils. Catchell soils have very strongly cemented or indurated duripans and have E horizons; Chilcott soils are greater than 152 cm to bedrock; Lookout soils have indurated duripans; Lovejoy soils have an indurated duripan do not have bedrock within 152 cm of the soil surface. Novacan, Pigtail, and Reno soils are greater than 152 cm to bedrock. Suncold soils do not have Bk horizons above the duripan.

GEOGRAPHIC SETTING: Bogusrim soils are on lava plateaus. These soils are formed in mixed volcanic ash and loess over residuum weathered from volcanic rock. Slopes are 2 to 15 percent. Elevations are 1,280 to 1,370 meters. The climate is semiarid with cool, moist winters and warm, dry summers. The mean annual precipitation is 200 to 280 mm; mean annual temperature is 7 to 8 degrees C, and the frost-free period is 80 to 100 days.

GEOGRAPHICALLY ASSOCIATED SOILS: These are the competing Suncold and Wisher soils. Wisher soils are very deep and have mollic epipedons.

DRAINAGE AND SATURATED HYDRAULIC CONDUCTIVITY: Well drained, very high runoff, slow to very slow permeability, moderately low saturated hydraulic conductivity.

USE AND VEGETATION: Rangeland and wildlife habitat. The present vegetation is mainly Wyoming big sagebrush and bluebunch wheatgrass.

DISTRIBUTION AND EXTENT: Southeast Oregon; the soil is of large extent. MLRA 25.

MLRA SOIL SURVEY REGIONAL OFFICE (MO) RESPONSIBLE: Davis, California.

SERIES PROPOSED: Malheur County, Oregon, Southern Part, 2008.

REMARKS: Diagnostic horizons and features recognized in this pedon are:
Ochric epipedon - The zone from the surface to 10 cm (A horizon).
Abrupt textural change - the boundary at 10 cm (between A and Bt1 horizons).
Argillic horizon - The zone from 10 cm to 52 cm (Bt1 and Bt2 horizons).
Ashy textures - Volcanic glass is 5 to 10 percent of the 0.02 to 2 mm fraction in the zone from 0 to 10 cm (A horizon).
Duripan - The zone from 82 to 130 cm (Bqkm1 and Bqkm2 horizons.
Particle-size control section - The zone from 10 cm to 52 cm. (Bt1 and Bt2 horizons).

ADDITIONAL DATA: Previous authors and editors include: SBF/ARR/TM

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National Cooperative Soil Survey
U.S.A.